/*
   Copyright (c) 2008-2012 Red Hat, Inc. <http://www.redhat.com>
   This file is part of GlusterFS.

   This file is licensed to you under your choice of the GNU Lesser
   General Public License, version 3 or any later version (LGPLv3 or
   later), or the GNU General Public License, version 2 (GPLv2), in all
   cases as published by the Free Software Foundation.
*/
#ifndef _CONFIG_H
#define _CONFIG_H
#include "config.h"
#endif

#include "dict.h"
#include "xlator.h"
#include "defaults.h"
#include "libxlator.h"
#include "common-utils.h"
#include "byte-order.h"
#include "marker-quota.h"
#include "marker-quota-helper.h"

int
mq_loc_copy (loc_t *dst, loc_t *src)
{
        int ret = -1;

        GF_VALIDATE_OR_GOTO ("marker", dst, out);
        GF_VALIDATE_OR_GOTO ("marker", src, out);

        if (src->inode == NULL ||
            ((src->parent == NULL) && (uuid_is_null (src->pargfid))
             && !__is_root_gfid (src->inode->gfid))) {
                gf_log ("marker", GF_LOG_WARNING,
                        "src loc is not valid");
                goto out;
        }

        ret = loc_copy (dst, src);
out:
        return ret;
}

int32_t
mq_get_local_err (quota_local_t *local,
                  int32_t *val)
{
        int32_t ret = -1;

        GF_VALIDATE_OR_GOTO ("marker", local, out);
        GF_VALIDATE_OR_GOTO ("marker", val, out);

        LOCK (&local->lock);
        {
                *val = local->err;
        }
        UNLOCK (&local->lock);

        ret = 0;
out:
        return ret;
}

int32_t
mq_get_ctx_updation_status (quota_inode_ctx_t *ctx,
                            gf_boolean_t *status)
{
        int32_t   ret = -1;

        GF_VALIDATE_OR_GOTO ("marker", ctx, out);
        GF_VALIDATE_OR_GOTO ("marker", status, out);

        LOCK (&ctx->lock);
        {
                *status = ctx->updation_status;
        }
        UNLOCK (&ctx->lock);

        ret = 0;
out:
        return ret;
}


int32_t
mq_set_ctx_updation_status (quota_inode_ctx_t *ctx,
                            gf_boolean_t status)
{
        int32_t   ret = -1;

        if (ctx == NULL)
                goto out;

        LOCK (&ctx->lock);
        {
                ctx->updation_status = status;
        }
        UNLOCK (&ctx->lock);

        ret = 0;
out:
        return ret;
}

int32_t
mq_test_and_set_ctx_updation_status (quota_inode_ctx_t *ctx,
                                     gf_boolean_t *status)
{
        int32_t         ret     = -1;
        gf_boolean_t    temp    = _gf_false;

        GF_VALIDATE_OR_GOTO ("marker", ctx, out);
        GF_VALIDATE_OR_GOTO ("marker", status, out);

        LOCK (&ctx->lock);
        {
                temp = *status;
                *status = ctx->updation_status;
                ctx->updation_status = temp;
        }
        UNLOCK (&ctx->lock);

        ret = 0;
out:
        return ret;
}

void
mq_assign_lk_owner (xlator_t *this, call_frame_t *frame)
{
        marker_conf_t *conf     = NULL;
        uint64_t       lk_owner = 0;

        conf = this->private;

        LOCK (&conf->lock);
        {
                if (++conf->quota_lk_owner == 0) {
                        ++conf->quota_lk_owner;
                }

                lk_owner = conf->quota_lk_owner;
        }
        UNLOCK (&conf->lock);

        set_lk_owner_from_uint64 (&frame->root->lk_owner, lk_owner);

        return;
}


int32_t
mq_loc_fill_from_name (xlator_t *this, loc_t *newloc, loc_t *oldloc,
                       uint64_t ino, char *name)
{
        int32_t   ret  = -1;
        int32_t   len  = 0;
        char     *path = NULL;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", newloc, out);
        GF_VALIDATE_OR_GOTO ("marker", oldloc, out);
        GF_VALIDATE_OR_GOTO ("marker", name, out);

        newloc->inode = inode_new (oldloc->inode->table);

        if (!newloc->inode) {
                ret = -1;
                goto out;
        }

        newloc->parent = inode_ref (oldloc->inode);
        uuid_copy (newloc->pargfid, oldloc->inode->gfid);

        if (!oldloc->path) {
                ret = loc_path (oldloc, NULL);
                if (ret == -1)
                        goto out;
        }

        len = strlen (oldloc->path);

        if (oldloc->path [len - 1] == '/')
                ret = gf_asprintf ((char **) &path, "%s%s",
                                   oldloc->path, name);
        else
                ret = gf_asprintf ((char **) &path, "%s/%s",
                                   oldloc->path, name);

        if (ret < 0)
                goto out;

        newloc->path = path;

        newloc->name = strrchr (newloc->path, '/');

        if (newloc->name)
                newloc->name++;

        gf_log (this->name, GF_LOG_DEBUG, "path = %s name =%s",
                newloc->path, newloc->name);
out:
        return ret;
}

int32_t
mq_dirty_inode_updation_done (call_frame_t *frame, void *cookie, xlator_t *this,
                              int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        QUOTA_STACK_DESTROY (frame, this);

        return 0;
}

int32_t
mq_release_lock_on_dirty_inode (call_frame_t *frame, void *cookie, xlator_t *this,
                                int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        struct gf_flock   lock  = {0, };
        quota_local_t    *local = NULL;
        loc_t             loc = {0, };
	int               ret = -1;

        local = frame->local;

        if (op_ret == -1) {
                local->err = -1;

                mq_dirty_inode_updation_done (frame, NULL, this, 0, 0, NULL);

                return 0;
        }

        if (op_ret == 0)
                local->ctx->dirty = 0;

        lock.l_type   = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start  = 0;
        lock.l_len    = 0;
        lock.l_pid    = 0;

        ret = loc_copy (&loc, &local->loc);
	if (ret == -1) {
                local->err = -1;
                frame->local = NULL;
                mq_dirty_inode_updation_done (frame, NULL, this, 0, 0, NULL);
                return 0;
        }

        if (local->loc.inode == NULL) {
                gf_log (this->name, GF_LOG_WARNING,
                        "Inode is NULL, so can't stackwind.");
                goto out;
        }

        STACK_WIND (frame,
                    mq_dirty_inode_updation_done,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &loc, F_SETLKW, &lock, NULL);

        loc_wipe (&loc);

        return 0;
out:
        mq_dirty_inode_updation_done (frame, NULL, this, -1, 0, NULL);

        return 0;
}

int32_t
mq_mark_inode_undirty (call_frame_t *frame, void *cookie, xlator_t *this,
                       int32_t op_ret, int32_t op_errno, dict_t *dict,
                       dict_t *xdata)
{
        int32_t        ret     = -1;
        int64_t       *size    = NULL;
        dict_t        *newdict = NULL;
        quota_local_t *local   = NULL;

        local = (quota_local_t *) frame->local;

        if (op_ret == -1)
                goto err;

        if (!dict)
                goto wind;

        ret = dict_get_bin (dict, QUOTA_SIZE_KEY, (void **) &size);
        if (ret)
                goto wind;

        LOCK (&local->ctx->lock);
        {
                local->ctx->size = ntoh64 (*size);
        }
        UNLOCK (&local->ctx->lock);

wind:
        newdict = dict_new ();
        if (!newdict)
                goto err;

        ret = dict_set_int8 (newdict, QUOTA_DIRTY_KEY, 0);
        if (ret)
                goto err;

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, local->loc.inode->gfid);

        GF_UUID_ASSERT (local->loc.gfid);
        STACK_WIND (frame, mq_release_lock_on_dirty_inode,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->setxattr,
                    &local->loc, newdict, 0, NULL);
        ret = 0;

err:
        if (op_ret == -1 || ret == -1) {
                local->err = -1;

                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);
        }

        if (newdict)
                dict_unref (newdict);

        return 0;
}

int32_t
mq_update_size_xattr (call_frame_t *frame, void *cookie, xlator_t *this,
                      int32_t op_ret, int32_t op_errno, inode_t *inode,
                      struct iatt *buf, dict_t *dict, struct iatt *postparent)
{
        int32_t          ret      = -1;
        dict_t          *new_dict = NULL;
        int64_t         *size     = NULL;
        int64_t         *delta    = NULL;
        quota_local_t   *local    = NULL;

        local = frame->local;

        if (op_ret == -1)
                goto err;

        if (dict == NULL) {
                gf_log (this->name, GF_LOG_WARNING,
                        "Dict is null while updating the size xattr %s",
                        local->loc.path?local->loc.path:"");
                goto err;
        }

        ret = dict_get_bin (dict, QUOTA_SIZE_KEY, (void **) &size);
        if (!size) {
                gf_log (this->name, GF_LOG_WARNING,
                        "failed to get the size, %s",
                        local->loc.path?local->loc.path:"");
                goto err;
        }

        QUOTA_ALLOC_OR_GOTO (delta, int64_t, ret, err);

        *delta = hton64 (local->sum - ntoh64 (*size));

        gf_log (this->name, GF_LOG_DEBUG, "calculated size = %"PRId64", "
                "original size = %"PRIu64
                " path = %s diff = %"PRIu64, local->sum, ntoh64 (*size),
                local->loc.path, ntoh64 (*delta));

        new_dict = dict_new ();
        if (!new_dict) {
		errno = ENOMEM;
		goto err;
	}

        ret = dict_set_bin (new_dict, QUOTA_SIZE_KEY, delta, 8);
        if (ret)
                goto err;

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, buf->ia_gfid);

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame, mq_mark_inode_undirty, FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->xattrop, &local->loc,
                    GF_XATTROP_ADD_ARRAY64, new_dict, NULL);

        ret = 0;

err:
        if (op_ret == -1 || ret == -1) {
                local->err = -1;
                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);
        }

        if (new_dict)
                dict_unref (new_dict);

        return 0;
}

int32_t
mq_test_and_set_local_err(quota_local_t *local,
                          int32_t *val)
{
        int     tmp = 0;
        int32_t ret = -1;

        GF_VALIDATE_OR_GOTO ("marker", local, out);
        GF_VALIDATE_OR_GOTO ("marker", val, out);

        LOCK (&local->lock);
        {
                tmp = local->err;
                local->err = *val;
                *val = tmp;
        }
        UNLOCK (&local->lock);

        ret = 0;
out:
        return ret;
}

int32_t
mq_get_dirty_inode_size (call_frame_t *frame, xlator_t *this)
{
        int32_t        ret   = -1;
        dict_t        *dict  = NULL;
        quota_local_t *local = NULL;

        local = (quota_local_t *) frame->local;

        dict = dict_new ();
        if (!dict) {
                ret = -1;
                goto err;
        }

        ret = dict_set_int64 (dict, QUOTA_SIZE_KEY, 0);
        if (ret)
                goto err;

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, local->loc.inode->gfid);

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame, mq_update_size_xattr, FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->lookup, &local->loc, dict);
        ret =0;

err:
        if (ret) {
                local->err = -1;

                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);
        }

        if (dict)
                dict_unref (dict);

        return 0;
}

int32_t
mq_get_child_contribution (call_frame_t *frame,
                           void *cookie,
                           xlator_t *this,
                           int32_t op_ret,
                           int32_t op_errno,
                           inode_t *inode,
                           struct iatt *buf,
                           dict_t *dict,
                           struct iatt *postparent)
{
        int32_t        ret                = -1;
        int32_t        val                = 0;
        char           contri_key [512]   = {0, };
        int64_t       *contri             = NULL;
        quota_local_t *local              = NULL;

        local = frame->local;

        frame->local = NULL;

        QUOTA_STACK_DESTROY (frame, this);

        if (op_ret == -1) {
                gf_log (this->name, GF_LOG_ERROR, "%s",
                        strerror (op_errno));
                val = -2;
                if (!mq_test_and_set_local_err (local, &val) &&
                    val != -2)
                        mq_release_lock_on_dirty_inode (local->frame, NULL,
                                                        this, 0, 0, NULL);

                goto exit;
        }

        ret = mq_get_local_err (local, &val);
        if (!ret && val == -2)
                goto exit;

        GET_CONTRI_KEY (contri_key, local->loc.inode->gfid, ret);
        if (ret < 0)
                goto out;

        if (!dict)
                goto out;

        if (dict_get_bin (dict, contri_key, (void **) &contri) == 0)
                local->sum += ntoh64 (*contri);

out:
        LOCK (&local->lock);
        {
                val = --local->dentry_child_count;
        }
        UNLOCK (&local->lock);

        if (val == 0) {
                mq_dirty_inode_readdir (local->frame, NULL, this,
                                        0, 0, NULL, NULL);
        }
        mq_local_unref (this, local);

        return 0;
exit:
        mq_local_unref (this, local);
        return 0;
}

int32_t
mq_readdir_cbk (call_frame_t *frame,
                void *cookie,
                xlator_t *this,
                int32_t op_ret,
                int32_t op_errno,
                gf_dirent_t *entries, dict_t *xdata)
{
        char           contri_key [512]   = {0, };
        int32_t        ret                = 0;
        int32_t        val                = 0;
        off_t          offset             = 0;
        int32_t        count              = 0;
        dict_t        *dict               = NULL;
        quota_local_t *local              = NULL;
        gf_dirent_t   *entry              = NULL;
        call_frame_t  *newframe           = NULL;
        loc_t          loc                = {0, };

        local = mq_local_ref (frame->local);

        if (op_ret == -1) {
                gf_log (this->name, GF_LOG_DEBUG,
                        "readdir failed %s", strerror (op_errno));
                local->err = -1;

                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);

                goto end;
        } else if (op_ret == 0) {
                mq_get_dirty_inode_size (frame, this);

                goto end;
        }

        local->dentry_child_count =  0;

        list_for_each_entry (entry, (&entries->list), list) {
                gf_log (this->name, GF_LOG_DEBUG, "entry  = %s", entry->d_name);

                if ((!strcmp (entry->d_name, ".")) || (!strcmp (entry->d_name,
                                                                ".."))) {
                        gf_log (this->name, GF_LOG_DEBUG, "entry  = %s",
                                entry->d_name);
                        continue;
                }

                offset = entry->d_off;
                count++;
        }

        if (count == 0) {
                mq_get_dirty_inode_size (frame, this);
                goto end;

        }

        local->frame = frame;

        LOCK (&local->lock);
        {
                local->dentry_child_count = count;
                local->d_off = offset;
        }
        UNLOCK (&local->lock);


        list_for_each_entry (entry, (&entries->list), list) {
                gf_log (this->name, GF_LOG_DEBUG, "entry  = %s", entry->d_name);

                if ((!strcmp (entry->d_name, ".")) || (!strcmp (entry->d_name,
                                                                ".."))) {
                        gf_log (this->name, GF_LOG_DEBUG, "entry  = %s",
                                entry->d_name);
                        continue;
                }

                ret = mq_loc_fill_from_name (this, &loc, &local->loc,
                                             entry->d_ino, entry->d_name);
                if (ret < 0) {
                        gf_log (this->name, GF_LOG_WARNING, "Couldn't build "
                                "loc for %s/%s, returning from updation of "
                                "quota attributes",
                                uuid_utoa (local->loc.inode->gfid),
                                entry->d_name);
                        goto out;
                }

                ret = 0;

                LOCK (&local->lock);
                {
                        if (local->err != -2) {
                                newframe = copy_frame (frame);
                                if (!newframe) {
                                        ret = -1;
                                }
                        } else
                                ret = -1;
                }
                UNLOCK (&local->lock);

                if (ret == -1)
                        goto out;

                newframe->local = mq_local_ref (local);

                dict = dict_new ();
                if (!dict) {
                        ret = -1;
                        goto out;
                }

                GET_CONTRI_KEY (contri_key, local->loc.inode->gfid, ret);
                if (ret < 0)
                        goto out;

                ret = dict_set_int64 (dict, contri_key, 0);
                if (ret)
                        goto out;

                STACK_WIND (newframe,
                            mq_get_child_contribution,
                            FIRST_CHILD(this),
                            FIRST_CHILD(this)->fops->lookup,
                            &loc, dict);

                offset = entry->d_off;

                loc_wipe (&loc);

                newframe = NULL;

        out:
                if (dict) {
                        dict_unref (dict);
                        dict = NULL;
                }

                if (ret) {
                        val = -2;
                        mq_test_and_set_local_err (local, &val);

                        if (newframe) {
                                newframe->local = NULL;
                                mq_local_unref(this, local);
                                QUOTA_STACK_DESTROY (newframe, this);
                        }

                        break;
                }
        }

        if (ret && val != -2) {
                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);
        }
end:
        mq_local_unref (this, local);

        return 0;
}

int32_t
mq_dirty_inode_readdir (call_frame_t *frame,
                        void *cookie,
                        xlator_t *this,
                        int32_t op_ret,
                        int32_t op_errno,
                        fd_t *fd, dict_t *xdata)
{
        quota_local_t *local = NULL;

        local = frame->local;

        if (op_ret == -1) {
                local->err = -1;
                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);
                return 0;
        }

        if (local->fd == NULL)
                local->fd = fd_ref (fd);

        STACK_WIND (frame,
                    mq_readdir_cbk,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->readdir,
                    local->fd, READDIR_BUF, local->d_off, xdata);

        return 0;
}

int32_t
mq_check_if_still_dirty (call_frame_t *frame,
                         void *cookie,
                         xlator_t *this,
                         int32_t op_ret,
                         int32_t op_errno,
                         inode_t *inode,
                         struct iatt *buf,
                         dict_t *dict,
                         struct iatt *postparent)
{
        int8_t           dirty          = -1;
        int32_t          ret            = -1;
        fd_t            *fd             = NULL;
        quota_local_t   *local          = NULL;

        local = frame->local;

        if (op_ret == -1) {
                gf_log (this->name, GF_LOG_ERROR, "failed to get "
                        "the dirty xattr for %s", local->loc.path);
                goto err;
        }

        if (!dict) {
                ret = -1;
                goto err;
        }

        ret = dict_get_int8 (dict, QUOTA_DIRTY_KEY, &dirty);
        if (ret)
                goto err;

        //the inode is not dirty anymore
        if (dirty == 0) {
                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);

                return 0;
        }

        fd = fd_create (local->loc.inode, frame->root->pid);

        local->d_off = 0;

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, buf->ia_gfid);

        GF_UUID_ASSERT (local->loc.gfid);
        STACK_WIND(frame,
                   mq_dirty_inode_readdir,
                   FIRST_CHILD(this),
                   FIRST_CHILD(this)->fops->opendir,
                   &local->loc, fd, NULL);

        ret = 0;

err:
        if (op_ret == -1 || ret == -1) {
                local->err = -1;
                mq_release_lock_on_dirty_inode (frame, NULL, this, 0, 0, NULL);
        }

        if (fd != NULL) {
                fd_unref (fd);
        }

        return 0;
}

int32_t
mq_get_dirty_xattr (call_frame_t *frame, void *cookie, xlator_t *this,
                    int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        int32_t        ret       = -1;
        dict_t        *xattr_req = NULL;
        quota_local_t *local     = NULL;

        if (op_ret == -1) {
                mq_dirty_inode_updation_done (frame, NULL, this, 0, 0, NULL);
                return 0;
        }

        local = frame->local;

        xattr_req = dict_new ();
        if (xattr_req == NULL) {
                ret = -1;
                goto err;
        }

        ret = dict_set_int8 (xattr_req, QUOTA_DIRTY_KEY, 0);
        if (ret)
                goto err;

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, local->loc.inode->gfid);

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame,
                    mq_check_if_still_dirty,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->lookup,
                    &local->loc,
                    xattr_req);
        ret = 0;

err:
        if (ret) {
                local->err = -1;
                mq_release_lock_on_dirty_inode(frame, NULL, this, 0, 0, NULL);
        }

        if (xattr_req)
                dict_unref (xattr_req);

        return 0;
}

/* return 1 when dirty updation started
 * 0 other wise
 */
int32_t
mq_update_dirty_inode (xlator_t *this,
                       loc_t *loc,
                       quota_inode_ctx_t *ctx,
                       inode_contribution_t *contribution)
{
        int32_t          ret        = -1;
        quota_local_t   *local      = NULL;
        gf_boolean_t    status     = _gf_false;
        struct gf_flock  lock       = {0, };
        call_frame_t    *frame      = NULL;

        ret = mq_get_ctx_updation_status (ctx, &status);
        if (ret == -1 || status == _gf_true) {
                ret = 0;
                goto out;
        }

        frame = create_frame (this, this->ctx->pool);
        if (frame == NULL) {
                ret = -1;
                goto out;
        }

        mq_assign_lk_owner (this, frame);

        local = mq_local_new ();
        if (local == NULL)
                goto fr_destroy;

        frame->local = local;
        ret = mq_loc_copy (&local->loc, loc);
        if (ret < 0)
                goto fr_destroy;

        local->ctx = ctx;

        local->contri = contribution;

        lock.l_type = F_WRLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = 0;
        lock.l_len = 0;

        if (local->loc.inode == NULL) {
                ret = -1;
                gf_log (this->name, GF_LOG_WARNING,
                        "Inode is NULL, so can't stackwind.");
                goto fr_destroy;
        }

        STACK_WIND (frame,
                    mq_get_dirty_xattr,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->loc, F_SETLKW, &lock, NULL);
        return 1;

fr_destroy:
        QUOTA_STACK_DESTROY (frame, this);
out:

        return 0;
}


int32_t
mq_inode_creation_done (call_frame_t *frame, void *cookie, xlator_t *this,
                        int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        quota_local_t *local = NULL;

        if (frame == NULL)
                return 0;

        local = frame->local;

        if (local != NULL) {
                mq_initiate_quota_txn (this, &local->loc);
        }

        QUOTA_STACK_DESTROY (frame, this);

        return 0;
}


int32_t
mq_xattr_creation_release_lock (call_frame_t *frame, void *cookie,
                                xlator_t *this, int32_t op_ret,
                                int32_t op_errno, dict_t *xdata)
{
        struct gf_flock  lock  = {0, };
        quota_local_t   *local = NULL;

        local = frame->local;

        lock.l_type   = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start  = 0;
        lock.l_len    = 0;
        lock.l_pid    = 0;

        STACK_WIND (frame,
                    mq_inode_creation_done,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->loc,
                    F_SETLKW, &lock, NULL);

        return 0;
}


int32_t
mq_create_dirty_xattr (call_frame_t *frame, void *cookie, xlator_t *this,
                       int32_t op_ret, int32_t op_errno, dict_t *dict,
                       dict_t *xdata)
{
        int32_t          ret       = -1;
        dict_t          *newdict   = NULL;
        quota_local_t   *local     = NULL;

        if (op_ret < 0) {
                goto err;
        }

        local = frame->local;

        if (local->loc.inode->ia_type == IA_IFDIR) {
                newdict = dict_new ();
                if (!newdict) {
                        goto err;
                }

                ret = dict_set_int8 (newdict, QUOTA_DIRTY_KEY, 0);
                if (ret == -1) {
                        goto err;
                }

                uuid_copy (local->loc.gfid, local->loc.inode->gfid);
                GF_UUID_ASSERT (local->loc.gfid);

                STACK_WIND (frame, mq_xattr_creation_release_lock,
                            FIRST_CHILD(this),
                            FIRST_CHILD(this)->fops->setxattr,
                            &local->loc, newdict, 0, NULL);
        } else {
                mq_xattr_creation_release_lock (frame, NULL, this, 0, 0, NULL);
        }

        ret = 0;

err:
        if (ret < 0) {
                mq_xattr_creation_release_lock (frame, NULL, this, 0, 0, NULL);
        }

        if (newdict != NULL)
                dict_unref (newdict);

        return 0;
}


int32_t
mq_create_xattr (xlator_t *this, call_frame_t *frame)
{
        int32_t               ret       = 0;
        int64_t              *value     = NULL;
        int64_t              *size      = NULL;
        dict_t               *dict      = NULL;
        char                  key[512]  = {0, };
        quota_local_t        *local     = NULL;
        quota_inode_ctx_t    *ctx       = NULL;
        inode_contribution_t *contri    = NULL;

        if (frame == NULL || this == NULL)
                return 0;

        local = frame->local;

        ret = mq_inode_ctx_get (local->loc.inode, this, &ctx);
        if (ret < 0) {
                ctx = mq_inode_ctx_new (local->loc.inode, this);
                if (ctx == NULL) {
                        gf_log (this->name, GF_LOG_WARNING,
                                "mq_inode_ctx_new failed");
                        ret = -1;
                        goto out;
                }
        }

        dict = dict_new ();
        if (!dict)
                goto out;

        if (local->loc.inode->ia_type == IA_IFDIR) {
                QUOTA_ALLOC_OR_GOTO (size, int64_t, ret, err);
                ret = dict_set_bin (dict, QUOTA_SIZE_KEY, size, 8);
                if (ret < 0)
                        goto free_size;
        }

        if ((local->loc.path && strcmp (local->loc.path, "/") != 0)
            || (local->loc.inode && !uuid_is_null (local->loc.inode->gfid) &&
                !__is_root_gfid (local->loc.inode->gfid))
            || (!uuid_is_null (local->loc.gfid)
                && !__is_root_gfid (local->loc.gfid))) {
                contri = mq_add_new_contribution_node (this, ctx, &local->loc);
                if (contri == NULL)
                        goto err;

                QUOTA_ALLOC_OR_GOTO (value, int64_t, ret, err);
                GET_CONTRI_KEY (key, local->loc.parent->gfid, ret);

                ret = dict_set_bin (dict, key, value, 8);
                if (ret < 0)
                        goto free_value;
        }

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame, mq_create_dirty_xattr, FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->xattrop, &local->loc,
                    GF_XATTROP_ADD_ARRAY64, dict, NULL);
        ret = 0;

free_size:
        if (ret < 0) {
                GF_FREE (size);
        }

free_value:
        if (ret < 0) {
                GF_FREE (value);
        }

err:
        dict_unref (dict);

out:
        if (ret < 0) {
                mq_xattr_creation_release_lock (frame, NULL, this, 0, 0, NULL);
        }

        return 0;
}


int32_t
mq_check_n_set_inode_xattr (call_frame_t *frame, void *cookie,
                            xlator_t *this, int32_t op_ret, int32_t op_errno,
                            inode_t *inode, struct iatt *buf, dict_t *dict,
                            struct iatt *postparent)
{
        quota_local_t        *local           = NULL;
        int64_t              *size            = NULL, *contri = NULL;
        int8_t                dirty           = 0;
        int32_t               ret             = 0;
        char                  contri_key[512] = {0, };

        if (op_ret < 0) {
                goto out;
        }

        local = frame->local;

        ret = dict_get_bin (dict, QUOTA_SIZE_KEY, (void **) &size);
        if (ret < 0)
                goto create_xattr;

        ret = dict_get_int8 (dict, QUOTA_DIRTY_KEY, &dirty);
        if (ret < 0)
                goto create_xattr;

        //check contribution xattr if not root
        if ((local->loc.path && strcmp (local->loc.path, "/") != 0)
            || (!uuid_is_null (local->loc.gfid)
                && !__is_root_gfid (local->loc.gfid))
            || (local->loc.inode
                && !uuid_is_null (local->loc.inode->gfid)
                && !__is_root_gfid (local->loc.inode->gfid))) {
                GET_CONTRI_KEY (contri_key, local->loc.parent->gfid, ret);
                if (ret < 0)
                        goto out;

                ret = dict_get_bin (dict, contri_key, (void **) &contri);
                if (ret < 0)
                        goto create_xattr;
        }

out:
        mq_xattr_creation_release_lock (frame, NULL, this, 0, 0, NULL);
        return 0;

create_xattr:
        if (uuid_is_null (local->loc.gfid)) {
                uuid_copy (local->loc.gfid, buf->ia_gfid);
        }

        mq_create_xattr (this, frame);
        return 0;
}


int32_t
mq_get_xattr (call_frame_t *frame, void *cookie, xlator_t *this,
              int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        dict_t        *xattr_req = NULL;
        quota_local_t *local     = NULL;
        int32_t        ret       = 0;

        if (op_ret < 0) {
                goto lock_err;
        }

        local = frame->local;

        xattr_req = dict_new ();
        if (xattr_req == NULL) {
                goto err;
        }

        ret = mq_req_xattr (this, &local->loc, xattr_req);
        if (ret < 0) {
                gf_log (this->name, GF_LOG_WARNING, "cannot request xattr");
                goto err;
        }

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, local->loc.inode->gfid);

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame, mq_check_n_set_inode_xattr, FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->lookup, &local->loc, xattr_req);

        dict_unref (xattr_req);

        return 0;

err:
        mq_xattr_creation_release_lock (frame, NULL, this, 0, 0, NULL);

        if (xattr_req)
                dict_unref (xattr_req);
        return 0;

lock_err:
        mq_inode_creation_done (frame, NULL, this, 0, 0, NULL);
        return 0;
}


int32_t
mq_set_inode_xattr (xlator_t *this, loc_t *loc)
{
        struct gf_flock  lock  = {0, };
        quota_local_t   *local = NULL;
        int32_t          ret   = 0;
        call_frame_t    *frame = NULL;

        frame = create_frame (this, this->ctx->pool);
        if (!frame) {
                ret = -1;
                goto err;
        }

        local = mq_local_new ();
        if (local == NULL) {
                goto err;
        }

        frame->local = local;

        ret = loc_copy (&local->loc, loc);
        if (ret < 0) {
                goto err;
        }

        frame->local = local;

        lock.l_len    = 0;
        lock.l_start  = 0;
        lock.l_type   = F_WRLCK;
        lock.l_whence = SEEK_SET;

        STACK_WIND (frame,
                    mq_get_xattr,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->loc, F_SETLKW, &lock, NULL);

        return 0;

err:
        QUOTA_STACK_DESTROY (frame, this);

        return 0;
}


int32_t
mq_get_parent_inode_local (xlator_t *this, quota_local_t *local)
{
        int32_t            ret = -1;
        quota_inode_ctx_t *ctx = NULL;
        inode_contribution_t *contribution = NULL;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", local, out);

        local->contri = NULL;

        loc_wipe (&local->loc);

        ret = mq_loc_copy (&local->loc, &local->parent_loc);
        if (ret < 0) {
                gf_log_callingfn (this->name, GF_LOG_WARNING,
                        "loc copy failed");
                goto out;
        }

        loc_wipe (&local->parent_loc);

        ret = mq_inode_loc_fill (NULL, local->loc.parent,
                                 &local->parent_loc);
        if (ret < 0) {
                gf_log_callingfn (this->name, GF_LOG_WARNING,
                        "failed to build parent loc of %s",
                        local->loc.path);
                goto out;
        }

        ret = mq_inode_ctx_get (local->loc.inode, this, &ctx);
        if (ret < 0) {
                gf_log_callingfn (this->name, GF_LOG_WARNING,
                                  "inode ctx get failed");
                goto out;
        }

        local->ctx = ctx;

        if (list_empty (&ctx->contribution_head)) {
                gf_log_callingfn (this->name, GF_LOG_WARNING,
                        "contribution node list is empty which "
                        "is an error");
                ret = -1;
                goto out;
        }

        /* Earlier we used to get the next entry in the list maintained
           by the context. In a good situation it works. i.e the next
           parent in the directory hierarchy for this path is obtained.

           But consider the below situation:
           mount-point: /mnt/point
           quota enabled directories within mount point: /a, /b, /c

           Now when some file (file1) in the directory /c is written some data,
           then to update the directories, marker has to get the contribution
           object for the parent inode, i.e /c.
           Beefore, it was being done by
           local->contri = (inode_contribution_t *) ctx->contribution_head.next;
           It works in the normal situations. But suppose /c is moved to /b.
           Now /b's contribution object is added to the end of the list of
           parents that the file file1 within /b/c is maintaining. Now if
           the file /b/c/file1 is copied to /b/c/new, to update the parent in
           the order c, b and / we cannot go to the next element in the list,
           as in this case the next contribution object would be / and /b's
           contribution will be at the end of the list. So get the proper
           parent's contribution, by searching the entire list.
        */
        contribution = mq_get_contribution_node (local->loc.parent, ctx);
        GF_ASSERT (contribution != NULL);
        local->contri = contribution;

        ret = 0;
out:
        return ret;
}


int32_t
mq_xattr_updation_done (call_frame_t *frame,
                        void *cookie,
                        xlator_t *this,
                        int32_t op_ret,
                        int32_t op_errno,
                        dict_t *dict, dict_t *xdata)
{
        QUOTA_STACK_DESTROY (frame, this);
        return 0;
}


int32_t
mq_inodelk_cbk (call_frame_t *frame, void *cookie,
                xlator_t *this, int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        int32_t         ret    = 0;
        gf_boolean_t    status = _gf_false;
        quota_local_t  *local  = NULL;

        local = frame->local;

        if (op_ret == -1 || local->err) {
                if (op_ret == -1) {
                        gf_log (this->name, GF_LOG_DEBUG,
                                "unlocking failed on path (%s)(%s)",
                                local->parent_loc.path, strerror (op_errno));
                }
                mq_xattr_updation_done (frame, NULL, this, 0, 0, NULL, NULL);

                return 0;
        }

        gf_log (this->name, GF_LOG_DEBUG,
                "inodelk released on %s", local->parent_loc.path);

        if ((strcmp (local->parent_loc.path, "/") == 0)
            || (local->delta == 0)) {
                mq_xattr_updation_done (frame, NULL, this, 0, 0, NULL, NULL);
        } else {
                ret = mq_get_parent_inode_local (this, local);
                if (ret < 0) {
                        mq_xattr_updation_done (frame, NULL, this, 0, 0, NULL,
                                                NULL);
                        goto out;
                }
                status = _gf_true;

                ret = mq_test_and_set_ctx_updation_status (local->ctx, &status);
                if (ret == 0 && status == _gf_false) {
                        mq_get_lock_on_parent (frame, this);
                } else {
                        mq_xattr_updation_done (frame, NULL, this, 0, 0, NULL,
                                                NULL);
                }
        }
out:
        return 0;
}


//now release lock on the parent inode
int32_t
mq_release_parent_lock (call_frame_t *frame, void *cookie,
                        xlator_t *this, int32_t op_ret,
                        int32_t op_errno, dict_t *xdata)
{
        int32_t            ret      = 0;
        quota_local_t     *local    = NULL;
        quota_inode_ctx_t *ctx      = NULL;
        struct gf_flock    lock     = {0, };

        local = frame->local;

        if (local->err != 0) {
                gf_log_callingfn (this->name,
                                  (local->err == ENOENT) ? GF_LOG_DEBUG
                                  : GF_LOG_WARNING,
                                  "An operation during quota updation "
                                  "of path (%s) failed (%s)", local->loc.path,
                                  strerror (local->err));
        }

        ret = mq_inode_ctx_get (local->parent_loc.inode, this, &ctx);
        if (ret < 0)
                goto wind;

        LOCK (&ctx->lock);
        {
                ctx->dirty = 0;
        }
        UNLOCK (&ctx->lock);

        if (local->parent_loc.inode == NULL) {
                gf_log (this->name, GF_LOG_DEBUG,
                        "Invalid parent inode.");
                goto err;
        }

wind:
        lock.l_type   = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start  = 0;
        lock.l_len    = 0;
        lock.l_pid    = 0;

        STACK_WIND (frame,
                    mq_inodelk_cbk,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->parent_loc,
                    F_SETLKW, &lock, NULL);

        return 0;
err:
        mq_xattr_updation_done (frame, NULL, this,
                                0, 0 , NULL, NULL);
        return 0;
}


int32_t
mq_mark_undirty (call_frame_t *frame,
                 void *cookie,
                 xlator_t *this,
                 int32_t op_ret,
                 int32_t op_errno,
                 dict_t *dict, dict_t *xdata)
{
        int32_t            ret          = -1;
        int64_t           *size         = NULL;
        dict_t            *newdict      = NULL;
        quota_local_t     *local        = NULL;
        quota_inode_ctx_t *ctx          = NULL;

        local = frame->local;

        if (op_ret == -1) {
                gf_log (this->name, GF_LOG_WARNING, "%s occurred while"
                        " updating the size of %s", strerror (op_errno),
                        local->parent_loc.path);

                goto err;
        }

        //update the size of the parent inode
        if (dict != NULL) {
                ret = mq_inode_ctx_get (local->parent_loc.inode, this, &ctx);
                if (ret < 0) {
                        op_errno = EINVAL;
                        goto err;
                }

                ret = dict_get_bin (dict, QUOTA_SIZE_KEY, (void **) &size);
                if (ret < 0) {
                        op_errno = EINVAL;
                        goto err;
                }

                LOCK (&ctx->lock);
                {
                        if (size)
                                ctx->size = ntoh64 (*size);
                        gf_log (this->name, GF_LOG_DEBUG, "%s %"PRId64,
                                local->parent_loc.path, ctx->size);
                }
                UNLOCK (&ctx->lock);
        }

        newdict = dict_new ();
        if (!newdict) {
                op_errno = ENOMEM;
                goto err;
        }

        ret = dict_set_int8 (newdict, QUOTA_DIRTY_KEY, 0);

        if (ret == -1) {
                op_errno = -ret;
                goto err;
        }

        uuid_copy (local->parent_loc.gfid, local->parent_loc.inode->gfid);
        GF_UUID_ASSERT (local->parent_loc.gfid);

        STACK_WIND (frame, mq_release_parent_lock,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->setxattr,
                    &local->parent_loc, newdict, 0, NULL);

        ret = 0;
err:
        if (op_ret == -1 || ret == -1) {
                local->err = op_errno;

                mq_release_parent_lock (frame, NULL, this, 0, 0, NULL);
        }

        if (newdict)
                dict_unref (newdict);

        return 0;
}


int32_t
mq_update_parent_size (call_frame_t *frame,
                       void *cookie,
                       xlator_t *this,
                       int32_t op_ret,
                       int32_t op_errno,
                       dict_t *dict, dict_t *xdata)
{
        int64_t             *size       = NULL;
        int32_t              ret        = -1;
        dict_t              *newdict    = NULL;
        quota_local_t       *local      = NULL;
        quota_inode_ctx_t   *ctx        = NULL;

        local = frame->local;

        if (op_ret == -1) {
                gf_log (this->name, ((op_errno == ENOENT) ? GF_LOG_DEBUG :
                                     GF_LOG_WARNING),
                        "xattrop call failed: %s", strerror (op_errno));

                goto err;
        }

        LOCK (&local->contri->lock);
        {
                local->contri->contribution += local->delta;
        }
        UNLOCK (&local->contri->lock);

        gf_log_callingfn (this->name, GF_LOG_DEBUG, "path: %s size: %"PRId64
                          " contribution:%"PRId64,
                          local->loc.path, local->ctx->size,
                          local->contri->contribution);

        if (dict == NULL) {
                op_errno = EINVAL;
                goto err;
        }

        ret = mq_inode_ctx_get (local->parent_loc.inode, this, &ctx);
        if (ret < 0) {
                op_errno = EINVAL;
                goto err;
        }

        newdict = dict_new ();
        if (!newdict) {
                op_errno = ENOMEM;
                ret = -1;
                goto err;
        }

        QUOTA_ALLOC_OR_GOTO (size, int64_t, ret, err);

        *size = hton64 (local->delta);

        ret = dict_set_bin (newdict, QUOTA_SIZE_KEY, size, 8);
        if (ret < 0) {
                op_errno = -ret;
                goto err;
        }

        if (uuid_is_null (local->parent_loc.gfid))
                        uuid_copy (local->parent_loc.gfid,
                                   local->parent_loc.inode->gfid);
        GF_UUID_ASSERT (local->parent_loc.gfid);

        STACK_WIND (frame,
                    mq_mark_undirty,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->xattrop,
                    &local->parent_loc,
                    GF_XATTROP_ADD_ARRAY64,
                    newdict, NULL);
        ret = 0;
err:
        if (op_ret == -1 || ret < 0) {
                local->err = op_errno;
                mq_release_parent_lock (frame, NULL, this, 0, 0, NULL);
        }

        if (newdict)
                dict_unref (newdict);

        return 0;
}

int32_t
mq_update_inode_contribution (call_frame_t *frame, void *cookie,
                              xlator_t *this, int32_t op_ret,
                              int32_t op_errno, inode_t *inode,
                              struct iatt *buf, dict_t *dict,
                              struct iatt *postparent)
{
        int32_t               ret              = -1;
        int64_t              *size             = NULL, size_int = 0, contri_int = 0;
        int64_t              *contri           = NULL;
        int64_t              *delta            = NULL;
        char                  contri_key [512] = {0, };
        dict_t               *newdict          = NULL;
        quota_local_t        *local            = NULL;
        quota_inode_ctx_t    *ctx              = NULL;
        inode_contribution_t *contribution     = NULL;

        local = frame->local;

        if (op_ret == -1) {
                gf_log (this->name, ((op_errno == ENOENT) ? GF_LOG_DEBUG :
                                     GF_LOG_WARNING),
                        "failed to get size and contribution of path (%s)(%s)",
                        local->loc.path, strerror (op_errno));
                goto err;
        }

        ctx = local->ctx;
        contribution = local->contri;

        //prepare to update size & contribution of the inode
        GET_CONTRI_KEY (contri_key, contribution->gfid, ret);
        if (ret == -1) {
                op_errno = ENOMEM;
                goto err;
        }

        LOCK (&ctx->lock);
        {
                if (local->loc.inode->ia_type == IA_IFDIR ) {
                        ret = dict_get_bin (dict, QUOTA_SIZE_KEY,
                                            (void **) &size);
                        if (ret < 0) {
                                op_errno = EINVAL;
                                goto unlock;
                        }

                        ctx->size = ntoh64 (*size);
                } else
                        ctx->size = buf->ia_blocks * 512;

                size_int = ctx->size;
        }
unlock:
        UNLOCK  (&ctx->lock);

        if (ret < 0) {
                goto err;
        }

        ret = dict_get_bin (dict, contri_key, (void **) &contri);

        LOCK (&contribution->lock);
        {
                if (ret < 0)
                        contribution->contribution = 0;
                else
                        contribution->contribution = ntoh64 (*contri);

                contri_int = contribution->contribution;
        }
        UNLOCK (&contribution->lock);

        gf_log (this->name, GF_LOG_DEBUG, "%s %"PRId64 " %"PRId64,
                local->loc.path, size_int, contri_int);

        local->delta = size_int - contri_int;

        if (local->delta == 0) {
                mq_mark_undirty (frame, NULL, this, 0, 0, NULL, NULL);
                return 0;
        }

        newdict = dict_new ();
        if (newdict == NULL) {
                op_errno = ENOMEM;
                ret = -1;
                goto err;
        }

        QUOTA_ALLOC_OR_GOTO (delta, int64_t, ret, err);

        *delta = hton64 (local->delta);

        ret = dict_set_bin (newdict, contri_key, delta, 8);
        if (ret < 0) {
                op_errno = -ret;
                ret = -1;
                goto err;
        }

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, buf->ia_gfid);

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame,
                    mq_update_parent_size,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->xattrop,
                    &local->loc,
                    GF_XATTROP_ADD_ARRAY64,
                    newdict, NULL);
        ret = 0;

err:
        if (op_ret == -1 || ret < 0) {
                local->err = op_errno;

                mq_release_parent_lock (frame, NULL, this, 0, 0, NULL);
        }

        if (newdict)
                dict_unref (newdict);

        return 0;
}

int32_t
mq_fetch_child_size_and_contri (call_frame_t *frame, void *cookie,
                                xlator_t *this, int32_t op_ret,
                                int32_t op_errno, dict_t *xdata)
{
        int32_t            ret              = -1;
        char               contri_key [512] = {0, };
        dict_t            *newdict          = NULL;
        quota_local_t     *local            = NULL;
        quota_inode_ctx_t *ctx              = NULL;

        local = frame->local;

        if (op_ret == -1) {
                gf_log (this->name, (op_errno == ENOENT) ? GF_LOG_DEBUG
                        : GF_LOG_WARNING,
                        "couldnt mark inode corresponding to path (%s) dirty "
                        "(%s)", local->parent_loc.path, strerror (op_errno));
                goto err;
        }

        VALIDATE_OR_GOTO (local->ctx, err);
        VALIDATE_OR_GOTO (local->contri, err);

        gf_log (this->name, GF_LOG_DEBUG, "%s marked dirty",
                local->parent_loc.path);

        //update parent ctx
        ret = mq_inode_ctx_get (local->parent_loc.inode, this, &ctx);
        if (ret == -1) {
                op_errno = EINVAL;
                goto err;
        }

        LOCK (&ctx->lock);
        {
                ctx->dirty = 1;
        }
        UNLOCK (&ctx->lock);

        newdict = dict_new ();
        if (newdict == NULL) {
                op_errno = ENOMEM;
                goto err;
        }

        if (local->loc.inode->ia_type == IA_IFDIR) {
                ret = dict_set_int64 (newdict, QUOTA_SIZE_KEY, 0);
                if (ret < 0) {
                        gf_log (this->name, GF_LOG_WARNING,
                                "dict_set failed.");
                        goto err;
                }
        }

        GET_CONTRI_KEY (contri_key, local->contri->gfid, ret);
        if (ret < 0) {
                op_errno = ENOMEM;
                goto err;
        }

        ret = dict_set_int64 (newdict, contri_key, 0);
        if (ret < 0) {
                gf_log (this->name, GF_LOG_WARNING,
                        "dict_set failed.");
                goto err;
        }

        mq_set_ctx_updation_status (local->ctx, _gf_false);

        if (uuid_is_null (local->loc.gfid))
                uuid_copy (local->loc.gfid, local->loc.inode->gfid);

        GF_UUID_ASSERT (local->loc.gfid);

        STACK_WIND (frame, mq_update_inode_contribution, FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->lookup, &local->loc, newdict);

        ret = 0;

err:
        if ((op_ret == -1) || (ret < 0)) {
                local->err = op_errno;

                mq_set_ctx_updation_status (local->ctx, _gf_false);

                mq_release_parent_lock (frame, NULL, this, 0, 0, NULL);
        }

        if (newdict)
                dict_unref (newdict);

        return 0;
}

int32_t
mq_markdirty (call_frame_t *frame, void *cookie,
              xlator_t *this, int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        int32_t        ret      = -1;
        dict_t        *dict     = NULL;
        quota_local_t *local    = NULL;

        local = frame->local;

        if (op_ret == -1){
                gf_log (this->name, (op_errno == ENOENT) ? GF_LOG_DEBUG
                        : GF_LOG_WARNING, "acquiring locks failed on %s (%s)",
                        local->parent_loc.path, strerror (op_errno));

                local->err = op_errno;

                mq_set_ctx_updation_status (local->ctx, _gf_false);

                mq_inodelk_cbk (frame, NULL, this, 0, 0, NULL);

                return 0;
        }

        gf_log (this->name, GF_LOG_TRACE,
                "inodelk succeeded on  %s", local->parent_loc.path);

        dict = dict_new ();
        if (!dict) {
                ret = -1;
                goto err;
        }

        ret = dict_set_int8 (dict, QUOTA_DIRTY_KEY, 1);
        if (ret == -1)
                goto err;

        uuid_copy (local->parent_loc.gfid,
                   local->parent_loc.inode->gfid);
        GF_UUID_ASSERT (local->parent_loc.gfid);

        STACK_WIND (frame, mq_fetch_child_size_and_contri,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->setxattr,
                    &local->parent_loc, dict, 0, NULL);

        ret = 0;
err:
        if (ret == -1) {
                local->err = 1;

                mq_set_ctx_updation_status (local->ctx, _gf_false);

                mq_release_parent_lock (frame, NULL, this, 0, 0, NULL);
        }

        if (dict)
                dict_unref (dict);

        return 0;
}


int32_t
mq_get_lock_on_parent (call_frame_t *frame, xlator_t *this)
{
        struct gf_flock  lock  = {0, };
        quota_local_t   *local = NULL;

        GF_VALIDATE_OR_GOTO ("marker", frame, fr_destroy);

        local = frame->local;
        gf_log (this->name, GF_LOG_DEBUG, "taking lock on %s",
                local->parent_loc.path);

        if (local->parent_loc.inode == NULL) {
                gf_log (this->name, GF_LOG_DEBUG,
                        "parent inode is not valid, aborting "
                        "transaction.");
                goto fr_destroy;
        }

        lock.l_len    = 0;
        lock.l_start  = 0;
        lock.l_type   = F_WRLCK;
        lock.l_whence = SEEK_SET;

        STACK_WIND (frame,
                    mq_markdirty,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->parent_loc, F_SETLKW, &lock, NULL);

        return 0;

fr_destroy:
        QUOTA_STACK_DESTROY (frame, this);

        return -1;
}

int
mq_prepare_txn_frame (xlator_t *this, loc_t *loc,
                      quota_inode_ctx_t *ctx,
                      inode_contribution_t *contri,
                      call_frame_t **new_frame)
{
        call_frame_t    *frame = NULL;
        int              ret   = -1;
        quota_local_t   *local = NULL;

        if (!this || !loc || !new_frame)
                goto err;

        frame = create_frame (this, this->ctx->pool);
        if (frame == NULL)
                goto err;

        mq_assign_lk_owner (this, frame);

        local = mq_local_new ();
        if (local == NULL)
                goto fr_destroy;

        frame->local = local;

        ret = mq_loc_copy (&local->loc, loc);
        if (ret < 0)
                goto fr_destroy;

        ret = mq_inode_loc_fill (NULL, local->loc.parent,
                                 &local->parent_loc);
        if (ret < 0)
                goto fr_destroy;

        local->ctx = ctx;
        local->contri = contri;

        ret = 0;
        *new_frame = frame;

        return ret;

fr_destroy:
        QUOTA_STACK_DESTROY (frame, this);
err:
        return ret;
}

int
mq_start_quota_txn (xlator_t *this, loc_t *loc,
                    quota_inode_ctx_t *ctx,
                    inode_contribution_t *contri)
{
        int32_t        ret      = -1;
        call_frame_t  *frame    = NULL;

        ret = mq_prepare_txn_frame (this, loc, ctx,
                                    contri, &frame);
        if (ret)
                goto err;

        ret = mq_get_lock_on_parent (frame, this);
        if (ret == -1)
                goto err;

        return 0;

err:
        mq_set_ctx_updation_status (ctx, _gf_false);

        return -1;
}


int
mq_initiate_quota_txn (xlator_t *this, loc_t *loc)
{
        int32_t               ret          = -1;
        gf_boolean_t          status       = _gf_false;
        quota_inode_ctx_t    *ctx          = NULL;
        inode_contribution_t *contribution = NULL;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", loc, out);
        GF_VALIDATE_OR_GOTO ("marker", loc->inode, out);

        ret = mq_inode_ctx_get (loc->inode, this, &ctx);
        if (ret == -1) {
                gf_log (this->name, GF_LOG_WARNING,
                        "inode ctx get failed, aborting quota txn");
                ret = -1;
                goto out;
        }

        /* Create the contribution node if its absent. Is it right to
           assume that if the contribution node is not there, then
           create one and proceed instead of returning?
           Reason for this assumption is for hard links. Suppose
           hard link for a file f1 present in a directory d1 is
           created in the directory d2 (as f2). Now, since d2's
           contribution is not there in f1's inode ctx, d2's
           contribution xattr wont be created and will create problems
           for quota operations.
        */
        contribution = mq_get_contribution_node (loc->parent, ctx);
        if (!contribution) {
                if ((loc->path && strcmp (loc->path, "/"))
                    || (!uuid_is_null (loc->gfid)
                        && !__is_root_gfid (loc->gfid))
                    || (loc->inode && !uuid_is_null (loc->inode->gfid)
                        && !__is_root_gfid (loc->inode->gfid)))
                        gf_log_callingfn (this->name, GF_LOG_TRACE,
                                          "contribution node for the "
                                          "path (%s) with parent (%s) "
                                          "not found", loc->path,
                                          loc->parent?
                                          uuid_utoa (loc->parent->gfid):
                                          NULL);

                contribution = mq_add_new_contribution_node (this, ctx, loc);
                if (!contribution) {
                        if(loc->path && strcmp (loc->path, "/"))
                                gf_log_callingfn (this->name, GF_LOG_WARNING,
                                                  "could not allocate "
                                                  " contribution node for (%s) "
                                                  "parent: (%s)", loc->path,
                                                  loc->parent?
                                                  uuid_utoa (loc->parent->gfid):
                                                  NULL);
                        goto out;
                }
        }

        /* To improve performance, do not start another transaction
         * if one is already in progress for same inode
         */
        status = _gf_true;

        ret = mq_test_and_set_ctx_updation_status (ctx, &status);
        if (ret < 0)
                goto out;

        if (status == _gf_false) {
                mq_start_quota_txn (this, loc, ctx, contribution);
        }

        ret = 0;
out:
        return ret;
}





int32_t
mq_inspect_directory_xattr (xlator_t *this,
                            loc_t *loc,
                            dict_t *dict,
                            struct iatt buf)
{
        int32_t               ret                 = 0;
        int8_t                dirty               = -1;
        int64_t              *size                = NULL, size_int = 0;
        int64_t              *contri              = NULL, contri_int = 0;
        char                  contri_key [512]    = {0, };
        gf_boolean_t          not_root            = _gf_false;
        quota_inode_ctx_t    *ctx                 = NULL;
        inode_contribution_t *contribution        = NULL;

        ret = mq_inode_ctx_get (loc->inode, this, &ctx);
        if (ret < 0) {
                ctx = mq_inode_ctx_new (loc->inode, this);
                if (ctx == NULL) {
                        gf_log (this->name, GF_LOG_WARNING,
                                "mq_inode_ctx_new failed");
                        ret = -1;
                        goto err;
                }
        }

        if (!loc->path || (loc->path && strcmp (loc->path, "/") != 0)) {
                contribution = mq_add_new_contribution_node (this, ctx, loc);
                if (contribution == NULL) {
                        if (!uuid_is_null (loc->inode->gfid))
                                gf_log (this->name, GF_LOG_DEBUG,
                                        "cannot add a new contribution node "
                                        "(%s)", uuid_utoa (loc->inode->gfid));
                        ret = -1;
                        goto err;
                }
        }

        ret = dict_get_bin (dict, QUOTA_SIZE_KEY, (void **) &size);
        if (ret < 0)
                goto out;

        ret = dict_get_int8 (dict, QUOTA_DIRTY_KEY, &dirty);
        if (ret < 0)
                goto out;

        if ((loc->path && strcmp (loc->path, "/") != 0)
            || (!uuid_is_null (loc->gfid) && !__is_root_gfid (loc->gfid))
            || (loc->inode && !uuid_is_null (loc->inode->gfid) &&
                !__is_root_gfid (loc->inode->gfid))) {
                not_root = _gf_true;

                GET_CONTRI_KEY (contri_key, contribution->gfid, ret);
                if (ret < 0)
                        goto out;

                ret = dict_get_bin (dict, contri_key, (void **) &contri);
                if (ret < 0)
                        goto out;

                LOCK (&contribution->lock);
                {
                        contribution->contribution = ntoh64 (*contri);
                        contri_int = contribution->contribution;
                }
                UNLOCK (&contribution->lock);
        }

        LOCK (&ctx->lock);
        {
                ctx->size = ntoh64 (*size);
                ctx->dirty = dirty;
                size_int = ctx->size;
        }
        UNLOCK (&ctx->lock);

        gf_log (this->name, GF_LOG_DEBUG, "size=%"PRId64
                " contri=%"PRId64, size_int, contri_int);

        if (dirty) {
                ret = mq_update_dirty_inode (this, loc, ctx, contribution);
        }

        if ((!dirty || ret == 0) && (not_root == _gf_true) &&
            (size_int != contri_int)) {
                mq_initiate_quota_txn (this, loc);
        }

        ret = 0;
out:
        if (ret)
                mq_set_inode_xattr (this, loc);
err:
        return ret;
}

int32_t
mq_inspect_file_xattr (xlator_t *this,
                       loc_t *loc,
                       dict_t *dict,
                       struct iatt buf)
{
        int32_t               ret              = -1;
        uint64_t              contri_int       = 0, size = 0;
        int64_t              *contri_ptr       = NULL;
        char                  contri_key [512] = {0, };
        quota_inode_ctx_t    *ctx              = NULL;
        inode_contribution_t *contribution     = NULL;

        ret = mq_inode_ctx_get (loc->inode, this, &ctx);
        if (ret < 0) {
                ctx = mq_inode_ctx_new (loc->inode, this);
                if (ctx == NULL) {
                        gf_log (this->name, GF_LOG_WARNING,
                                "mq_inode_ctx_new failed");
                        ret = -1;
                        goto out;
                }
        }

        contribution = mq_add_new_contribution_node (this, ctx, loc);
        if (contribution == NULL) {
                gf_log_callingfn (this->name, GF_LOG_DEBUG, "cannot allocate "
                                  "contribution node (path:%s)", loc->path);
                goto out;
        }

        LOCK (&ctx->lock);
        {
                ctx->size = 512 * buf.ia_blocks;
                size = ctx->size;
        }
        UNLOCK (&ctx->lock);

        list_for_each_entry (contribution, &ctx->contribution_head,
                             contri_list) {
                GET_CONTRI_KEY (contri_key, contribution->gfid, ret);
                if (ret < 0)
                        continue;

                ret = dict_get_bin (dict, contri_key, (void **) &contri_int);
                if (ret == 0) {
                        contri_ptr = (int64_t *)(unsigned long)contri_int;

                        LOCK (&contribution->lock);
                        {
                                contribution->contribution = ntoh64 (*contri_ptr);
                                contri_int = contribution->contribution;
                        }
                        UNLOCK (&contribution->lock);

                        gf_log (this->name, GF_LOG_DEBUG,
                                "size=%"PRId64 " contri=%"PRId64, size, contri_int);

                        if (size != contri_int) {
                                mq_initiate_quota_txn (this, loc);
                        }
                } else {
                        if (size)
                                mq_initiate_quota_txn (this, loc);
                        else
                                mq_set_inode_xattr (this, loc);
                }
        }

out:
        return ret;
}

int32_t
mq_xattr_state (xlator_t *this,
                loc_t *loc,
                dict_t *dict,
                struct iatt buf)
{
        if (((buf.ia_type == IA_IFREG) && !dht_is_linkfile (&buf, dict))
            || (buf.ia_type == IA_IFLNK))  {
                mq_inspect_file_xattr (this, loc, dict, buf);
        } else if (buf.ia_type == IA_IFDIR)
                mq_inspect_directory_xattr (this, loc, dict, buf);

        return 0;
}

int32_t
mq_req_xattr (xlator_t *this,
              loc_t *loc,
              dict_t *dict)
{
        int32_t               ret       = -1;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", dict, out);

        if (!loc)
                goto set_size;

        //if not "/" then request contribution
        if (loc->path && strcmp (loc->path, "/") == 0)
                goto set_size;

        ret = mq_dict_set_contribution (this, dict, loc);
        if (ret == -1)
                goto out;

set_size:
        ret = dict_set_uint64 (dict, QUOTA_SIZE_KEY, 0);
        if (ret < 0) {
                ret = -1;
                goto out;
        }

        ret = dict_set_int8 (dict, QUOTA_DIRTY_KEY, 0);
        if (ret < 0) {
                ret = -1;
                goto out;
        }

        ret = 0;

out:
        return ret;
}


int32_t
mq_removexattr_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                    int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        QUOTA_STACK_DESTROY (frame, this);

        return 0;
}

int32_t
_mq_inode_remove_done (call_frame_t *frame, void *cookie, xlator_t *this,
                       int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        int32_t        ret                = 0;
        char           contri_key [512]   = {0, };
        quota_local_t *local              = NULL;
        inode_t       *inode              = NULL;
        dentry_t      *tmp                = NULL;
        gf_boolean_t  last_dentry         = _gf_true;
        loc_t         loc                 = {0, };
        dentry_t      *other_dentry       = NULL;
        gf_boolean_t  remove              = _gf_false;

        local = (quota_local_t *) frame->local;

        if (op_ret == -1 || local->err == -1) {
                mq_removexattr_cbk (frame, NULL, this, -1, 0, NULL);
                return 0;
        }

        frame->local = NULL;

        GET_CONTRI_KEY (contri_key, local->contri->gfid, ret);

        if (!local->loc.inode)
                inode = inode_grep (local->loc.parent->table, local->loc.parent,
                                    local->loc.name);
        else
                inode = inode_ref (local->loc.inode);

        /* Suppose there are 2 directories dir1 and dir2. Quota limit is set on
           both the directories. There is a file (f1) in dir1. A hark link is
           created for that file inside the directory dir2 (say f2). Now one
           more xattr is set in the inode as a new hard link is created in a
           separate directory.
           i.e trusted.glusterfs.quota.<gfid of dir2>.contri=<contribution>

           Now when the hardlink f2 is removed, then the new xattr added (i.e
           the xattr indicating its contribution to ITS parent directory) should
           be removed (IFF there is not another hardlink for that file in the
           same directory).

           To do that upon getting unlink first check whether any other hard
           links for the same inode exists in the same directory. If so do not
           do anything and proceed for quota transaction.
           Otherwise, if the removed entry was the only link for that inode
           within that directory, then get another dentry for the inode
           (by traversing the list of dentries for the inode) and using the
           the dentry's parent and name, send removexattr so that the xattr
           is removed.

           If it is not done, then if the volume is restarted or the brick
           process is restarted, then wrong quota usage will be shown for the
           directory dir2.
        */
        if (inode) {
                tmp = NULL;
                list_for_each_entry (tmp, &inode->dentry_list, inode_list) {
                        if (local->loc.parent == tmp->parent) {
                                if (strcmp (local->loc.name, local->loc.name)) {
                                        last_dentry = _gf_false;
                                        break;
                                }
                        }
                }
                remove = last_dentry;
        }

        if (remove) {
                if (!other_dentry)    {
                        list_for_each_entry (tmp, &inode->dentry_list,
                                             inode_list) {
                                if (local->loc.parent != tmp->parent) {
                                        other_dentry = tmp;
                                        break;
                                }
                        }
                }

                if (!other_dentry)
                        mq_removexattr_cbk (frame, NULL, this, 0, 0, NULL);
                else {
                        loc.parent = inode_ref (other_dentry->parent);
                        loc.name = gf_strdup (other_dentry->name);
                        uuid_copy (loc.pargfid , other_dentry->parent->gfid);
                        loc.inode = inode_ref (inode);
                        uuid_copy (loc.gfid, inode->gfid);
                        inode_path (other_dentry->parent, other_dentry->name,
                                    (char **)&loc.path);

                        STACK_WIND (frame, mq_removexattr_cbk,
                                    FIRST_CHILD(this),
                                    FIRST_CHILD(this)->fops->removexattr,
                                    &loc, contri_key, NULL);
                }
        } else
                mq_removexattr_cbk (frame, NULL, this, 0, 0, NULL);

        ret = 0;

        if (strcmp (local->parent_loc.path, "/") != 0) {
                ret = mq_get_parent_inode_local (this, local);
                if (ret < 0)
                        goto out;

                mq_start_quota_txn (this, &local->loc, local->ctx, local->contri);
        }
out:
        mq_local_unref (this, local);

        loc_wipe (&loc);
        inode_unref (inode);
        return 0;
}

int32_t
mq_inode_remove_done (call_frame_t *frame, void *cookie, xlator_t *this,
                      int32_t op_ret, int32_t op_errno, dict_t *dict,
                      dict_t *xdata)
{
        int32_t            ret   = -1;
        struct gf_flock    lock  = {0, };
        quota_inode_ctx_t *ctx   = NULL;
        quota_local_t     *local = NULL;
        int64_t contribution = 0;

        local = frame->local;
        if (op_ret == -1)
                local->err = -1;

        ret = mq_inode_ctx_get (local->parent_loc.inode, this, &ctx);

        LOCK (&local->contri->lock);
        {
                contribution = local->contri->contribution;
        }
        UNLOCK (&local->contri->lock);

        if (contribution == local->size) {
                if (ret == 0) {
                        LOCK (&ctx->lock);
                        {
                                ctx->size -= contribution;
                        }
                        UNLOCK (&ctx->lock);

                        LOCK (&local->contri->lock);
                        {
                                local->contri->contribution = 0;
                        }
                        UNLOCK (&local->contri->lock);
                }
        }

        lock.l_type   = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start  = 0;
        lock.l_len    = 0;
        lock.l_pid    = 0;

        STACK_WIND (frame,
                    _mq_inode_remove_done,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->parent_loc,
                    F_SETLKW, &lock, NULL);
        return 0;
}

int32_t
mq_reduce_parent_size_xattr (call_frame_t *frame, void *cookie, xlator_t *this,
                             int32_t op_ret, int32_t op_errno, dict_t *xdata)
{
        int32_t                  ret               = -1;
        int64_t                 *size              = NULL;
        dict_t                  *dict              = NULL;
        quota_local_t           *local             = NULL;

        local = frame->local;
        if (op_ret == -1) {
                gf_log (this->name, GF_LOG_WARNING,
                        "inodelk set failed on %s", local->parent_loc.path);
                QUOTA_STACK_DESTROY (frame, this);
                return 0;
        }

        VALIDATE_OR_GOTO (local->contri, err);

        dict = dict_new ();
        if (dict == NULL) {
                ret = -1;
                goto err;
        }

        QUOTA_ALLOC_OR_GOTO (size, int64_t, ret, err);

        *size = hton64 (-local->size);

        ret = dict_set_bin (dict, QUOTA_SIZE_KEY, size, 8);
        if (ret < 0)
                goto err;

        uuid_copy (local->parent_loc.gfid,
                   local->parent_loc.inode->gfid);
        GF_UUID_ASSERT (local->parent_loc.gfid);

        STACK_WIND (frame, mq_inode_remove_done, FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->xattrop, &local->parent_loc,
                    GF_XATTROP_ADD_ARRAY64, dict, NULL);
        dict_unref (dict);
        return 0;

err:
        local->err = 1;
        mq_inode_remove_done (frame, NULL, this, -1, 0, NULL, NULL);
        if (dict)
                dict_unref (dict);
        return 0;
}

int32_t
mq_reduce_parent_size (xlator_t *this, loc_t *loc, int64_t contri)
{
        int32_t                  ret           = -1;
        struct gf_flock          lock          = {0,};
        call_frame_t            *frame         = NULL;
        quota_local_t           *local         = NULL;
        quota_inode_ctx_t       *ctx           = NULL;
        inode_contribution_t    *contribution  = NULL;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", loc, out);

        ret = mq_inode_ctx_get (loc->inode, this, &ctx);
        if (ret < 0)
                goto out;

        contribution = mq_get_contribution_node (loc->parent, ctx);
        if (contribution == NULL) {
                gf_log_callingfn (this->name, GF_LOG_WARNING, "contribution for"
                                  " the node %s is NULL", loc->path);
                goto out;
        }

        local = mq_local_new ();
        if (local == NULL) {
                ret = -1;
                goto out;
        }

        if (contri >= 0) {
                local->size = contri;
        } else {
                LOCK (&contribution->lock);
                {
                        local->size = contribution->contribution;
                }
                UNLOCK (&contribution->lock);
        }

        if (local->size == 0) {
                gf_log_callingfn (this->name, GF_LOG_TRACE,
                                  "local->size is 0 " "path: (%s)", loc->path);
                ret = 0;
                goto out;
        }

        ret = mq_loc_copy (&local->loc, loc);
        if (ret < 0)
                goto out;

        local->ctx = ctx;
        local->contri = contribution;

        ret = mq_inode_loc_fill (NULL, loc->parent, &local->parent_loc);
        if (ret < 0) {
                gf_log_callingfn (this->name, GF_LOG_INFO, "building parent loc"
                                  " failed. (gfid: %s)",
                                  uuid_utoa (loc->parent->gfid));
                goto out;
        }

        frame = create_frame (this, this->ctx->pool);
        if (!frame) {
                ret = -1;
                goto out;
        }

        mq_assign_lk_owner (this, frame);

        frame->local = local;

        lock.l_len    = 0;
        lock.l_start  = 0;
        lock.l_type   = F_WRLCK;
        lock.l_whence = SEEK_SET;

        if (local->parent_loc.inode == NULL) {
                ret = -1;
                gf_log (this->name, GF_LOG_DEBUG,
                        "Inode is NULL, so can't stackwind.");
                goto out;
        }

        STACK_WIND (frame,
                    mq_reduce_parent_size_xattr,
                    FIRST_CHILD(this),
                    FIRST_CHILD(this)->fops->inodelk,
                    this->name, &local->parent_loc, F_SETLKW, &lock, NULL);
        local = NULL;
        ret = 0;

out:
        if (local != NULL)
                mq_local_unref (this, local);

        return ret;
}


int32_t
init_quota_priv (xlator_t *this)
{
        return 0;
}


int32_t
mq_rename_update_newpath (xlator_t *this, loc_t *loc)
{
        int32_t               ret          = -1;
        quota_inode_ctx_t    *ctx          = NULL;
        inode_contribution_t *contribution = NULL;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", loc, out);
        GF_VALIDATE_OR_GOTO ("marker", loc->inode, out);

        ret = mq_inode_ctx_get (loc->inode, this, &ctx);
        if (ret < 0)
                goto out;

        contribution = mq_add_new_contribution_node (this, ctx, loc);
        if (contribution == NULL) {
                ret = -1;
                goto out;
        }

        mq_initiate_quota_txn (this, loc);
out:
        return ret;
}

int32_t
mq_forget (xlator_t *this, quota_inode_ctx_t *ctx)
{
        inode_contribution_t *contri = NULL;
        inode_contribution_t *next   = NULL;

        GF_VALIDATE_OR_GOTO ("marker", this, out);
        GF_VALIDATE_OR_GOTO ("marker", ctx, out);

        list_for_each_entry_safe (contri, next, &ctx->contribution_head,
                                  contri_list) {
                list_del (&contri->contri_list);
                GF_FREE (contri);
        }

        LOCK_DESTROY (&ctx->lock);
        GF_FREE (ctx);
out:
        return 0;
}
